1. Field of the Invention
This invention relates to novel catalyst compositions. The invention also relates to processes utilizing such compositions for codimerization, oligomerization or polymerization of olefins. In particular, this invention relates to a solid phase catalyst composition having a solid, acidic silica-based support, which catalyst exhibits unusual activity.
2. Description of the Prior Art
Numerous catalysts have been disclosed in the prior art as suitable for the preparation of addition products of olefins. Certain of these are useful for the preparation of low molecular weight dimers, trimers, tetramers, and the like. Others are used for the preparation of high molecular weight addition products, such as polymers and copolymers. The polymeric and oligomeric products derived from the catalytic addition reactions are often valuable materials in the petrochemical, fuel, and plastics industries, and the like.
Commonly used catalyst systems having catalytic activity for the preparation of oligomers and low molecular weight polymers are the homogenous liquid phase organophosphine complexes of transition metals such as iron, cobalt and nickel. Often included in such catalyst systems is a reducing agent, such as an alkyl aluminum halide, for example, ethylaluminum sesquichloride, to create a more active species of the catalyst. Such complex catalysts are often prepared by contacting the transition metal, ordinarily as a salt, with an organophosphine at ambient or elevated temperatures to provide a complex in an inert solvent. The reducing agent is added to the complex in the solvent to provide an active species.
Although the general scheme of these systems has been varied within considerable limits, the prior art describes liquid phase catalyst systems. Such systems have a number of disadvantages. For example, they present a materials handling problem and are not readily and completely separated from the low molecular weight oligomers and polymers commonly produced by such catalyst systems.
A solid phase catalyst would overcome these problems and therefore would be highly advantageous for this reason alone. Beyond this, however, it would be highly desirable for such solid catalysts to also exhibit significant activity for codimerization of different olefins. Olefins having different numbers of carbon atoms also have different reactivities and it has heretofore been difficult to codimerize different olefins utilizing the catalyst systems with effectiveness. Rather, when different olefins are contacted with the prior art catalysts of the above discussed type, codimers are usually produced in only minor amounts, while homodimers of each feed material predominate.